Modern surgical procedures attempt to minimize the invasive aspects of surgery. This is the result of the widely accepted belief that patient discomfort, overall recovery time, as well as the likelihood of post-surgical complications are generally proportional to the invasiveness of the particular procedure.
One way to reduce the invasiveness of surgical procedures such as exploratory surgery is through the use of endoscopes. Endoscopy is a surgical procedure where a thin scope is placed into the person being examined. Some specific examples include laparoscopy, where a scope is placed into the abdominal cavity, esophascopy, where the scope is placed into the esophagus, and arthroscopy, where the scope is placed into a joint.
Using endoscopes, the surgeon is able to view the interior of the person's body without the necessity of making a large incision. Instead, the endoscope, which includes a thin, insertable probe, requires only a small incision or hole into which the probe is inserted. It is the reduced trauma at the entry point which results in the reduced recovery time and reduced post-surgical complications such as infections or ruptured suture lines. Reduced trauma results because both the skin and the musculature are only minimally disturbed.
The rapidly expanding uses for endoscopy require new types of instruments which are minimally invasive. For example, in an esophascopy procedure which seeks to allow a surgeon to inspect a person's esophagus and/or stomach, the probe of the esophascope is placed into the esophagus and/or into the stomach.
Typical esophascopes are structurally representative of other types of endoscopes. For example, the probe portion typically includes a relatively rigid outer tube which contains an image guide as well as a light source. The image guide and light source are often optical fibers. The light source is used to illuminate the area adjacent the tip of the probe of the scope. Light reflected by objects is picked up by a lens which is also at the tip of the probe. The lens then directs the reflected light into the image guide which transfers the light to a video camera or other imaging means.
Importantly, it is the rigid outer tube which contains the components comprising the probe of the esophascope. Moreover, the outer tube cooperates with the other components to keep the lens fixed in front of the image guide. As noted above, the outer tube is typically relatively rigid. For most applications, this rigidity is beneficial to allow the probe to be forced into the portion of the body being viewed.
New applications of endoscopy have indicated that this rigidity is not always required, and is sometimes detrimental. For example, during esophascopy, a tool placed into the esophagus has a relatively large lumen in which to travel. Moreover, it is common to place an intubation tube into the esophagus. Accordingly, a rigid probe is not required to advance the tool through the esophagus. A scope having a flexible probe could be used by allowing the flexible probe to follow the curvatures of either the esophagus or the intubation tube.
Similarly, new exploratory surgical procedures are being envisioned where a flexible scope could be inserted into the vertebral canal. Once in the canal the scope could be used to inspect disc or nerve damage. A key limitation on these surgical techniques is the flexibility of the scope probe. Without sufficient flexibility, the likelihood of unintended trauma is too great to perform the endoscopy procedure.
There are also situations where a surgeon may have the tool enter the body in a first direction, but wish to view in a second direction. This is often the case where bones or organs cannot be moved out of the path of the scope. In these situations, a rigid scope cannot provide the desired body entry and views. This is especially true where endoscopy is used to view the inside of the spinal column.
In light of the above, it is an object of the present invention to provide a flexible fiber optic scope. It is also an object of the present invention to provide a scope which is sufficiently flexible to allow biasing of the scope tip, with the aid of a deflecting catheter, to provide a greater degree of viewing once the probe is placed within the body. Still further, it is an object of the present invention to provide an endoscope fiber optic bundle and lens system which can be used with or without a deflecting catheter. It is also an object of the present invention to provide an endoscope which can be scaled down to an outside diameter of 1 mm or less and still possess the required flexibility. Further, it is an object of the present invention to provide an endoscope which is relatively inexpensive to manufacture and comparatively easy and cost effective to use.